| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress the backlash of a support column with respect to a support cylindrical body.SOLUTION: The present invention provides a support device comprising a rotational-position return mechanism provided between a support cylindrical body and a support column, for returning the support column to a reference position for the rotation of the support column with respect to the support cylindrical body by a reduction in rotation torque applied to one end of the support column. The rotational-position return mechanism includes a guide member that is fixed into the support cylindrical body so as not to be rotatable, that is penetrated by the support column rotatably, and that has a first inclined surface formed on one axial end thereof; a rotational member on which a second inclined surface slidably contacting the first inclined surface of the guide member is formed, that rotates along with the support column, and that is provided to be axially movable with respect to the support column; an urging member that urges the guide member and the rotational member to axially approach each other; and a support member that is axially, slidably fitted into an outer circumference of the support column and that axially supports the urging member, a movement of the support column in a radial direction being suppressed between an inner circumference of the guide member and an inner circumference of the support member.</p> |
